Carroting animal hair and wool



Patented Apr. 23, 1929.

UNITED STATES PATENT OFFICE.

. ERICH 3611M, or VIENNA, AUSTRIA.

CARROTING ANIMAL HAIR AN D WOOL.

No Drawing. Application filed January 6, 1928, Serial No. 245,058, and in Austria February 9, 1927.

My invention relates-to carroting animal hair and wool that is to say to preparlng these materials for felting.

The ordinary and universally practiced method for carroting animal hair consists in treating the same with an aqueous solution of mercury nitrate and nitric acid. 4

It was assumed that in this carroting method the nitric acid acted as an'oxidizing agent on the hair. The use of mercury being highly objectionable for hygienic reasons, it has been proposed to use nitric acid alone, but it was found that for obtaining an adequate carroting effect the concentrat on of the nitric. acid was far too high for practical purposes and that hair so treated could not be kept on store because the oxidation continued even after the treatment, whereby the hair was made brittle and soon entirely lost its felting capacity. It has also been proposed to use other oxidizing agents for carroting hair such as peroxide of hydrogen, but in, this case too the concentrations necessary for obtaining the desired result were too high for practical purposes.

The object of my invention is to provide a process for carroting animal hair and wool which entirely avoids the use of mercury and permits to use solutions of a comparatively low concentration.

I have discovered that all oxidizing agents, even in low concentration may be caused to readily exert an oxidizing action on animal hair andwool resulting in a very satisfactory preparation of the same for felting by adding to such oxidizing agents substances, hereinafter called oxygen conveyors, which facilitate the transfer of oxygen from the oxidizing agent to the animal hair and wool.

tempt to give an exact theory of the part played by the oxygen conveyors in my improved process I may say that manyof the oxygen conveyors seem to takefpart in the reaction by taking up oxygen from the oxidizing agent and then giving off such oxygen to the animal hair and wool thus beingreduced again, while other oxygen conveyors deposited in. a finely subdivided colloidal state on the hair or wool seem to exert only a i simple catalytic or contact action without directly taking part in the r'eaction, or it may be, that even those oxygen conveyors which apparently take part in the chemical reaction alsoexert catalytic or contact action, say by forming temporary deposits or precipitates While I do not Wish to be understood to aton the hair or wool. Or it may even be that the hair and wool itself exerts or enhances catalytic action.

As a matter of fact I have found that suitable oxygen conveyors are salts soluble in ,water of metals capable of forminga plurality of oxygen compounds or oxides, the lower oxides being the more stable ones while being readily oxidizable by oxidizing agents. Such salts are those of silver, copper, lead, zirconium, bismuth, manganese, nickel, cobalt, iron, cadmium, cerium, chromium,

tungsten and molybdenum and I prefer to use the chlorides of the said metals, provided they be soluble in water. As oxidizing agents I may use any oxygen carriers and the oxygen acids and salts of oxygen acids of the metals of the chromium group soluble in Water that is to say any compounds rich in and readily parting with oxygen. Such oxygen carriers are peroxide of hydrogen, the oxygen acids of halogens, persulphuric acid, Caros acid or the salts of such acidsin aeidulated solutions, or mixtures of the said substances.

The oxygen conveyors to be used to the greatest advantage 1n anypartlcular case depend on the nature of the oxygen carrier. used. Thus when I use the highly reactive peroxide of hydrogen as an oxygen carrier, oxygen conveyors of comparatively low re- .activeness are preferably used such as salts of copper, cobalt, nickel, iron, lead, silver,

tungsten, molybdenum and the like, while when the oxygen carrier used is of comparatively lower reactiveness or partsless readily with its oxygen, such as chlora-tes or persulphates, an oxygen carrier of a comparatively higher reactiveness has to be used such agents, I use sulphuric acid, or nitric acid;

the latter then acts not only as an acidulating agent, but also'as an oxygen carrier. In this case'the oxygen carrier consists of a mixture of nitric acid and another oxygen carrier as above indicated. When peroxide of hydro-- gen 1s used as an-oxygen earner, an ac1dulat-- ing agent need not be used. The oxygen carrier and the oxygen conveyor are as a rule the oxygen carrier.

The concentrations of the solutions used are so low that they have no detrnnental action on the hair or Wool.

Emdmplcs. 1. To hair and wool on the skin is applied a mixture of an aqueous solution containing 6 to 10% by Weight of peroxide of hydrogen serving as an oxygen carrier and 1 to 2% of bismuth, cobalt or cerium 1n the form of a saltsoluble in water by spraying or brushing or in any other known or preferred manner. The skins are then dried at a temperature of to 100 cent-igrade. The hair and Wool will'bc found to be thoroughly carroted and may then be further worked in the well knoWn manner.

2. To hair or wool on the skin is applied, as in Example 1, an aqueous solution containing 5 to 10%.by Weight of nitric acid 3 to 5% of peroxide of hydrogen and 1 to 2% of silver, lead, zirconium, bismuth, manganese, nickel, cobalt, iron, cadmium or cerium, in the form of a salt soluble in water, the said salts acting as oxygen conveyors while the peroxide of hydrogen acts as an oxygen carrier, and the nitric acid as an acidulating agent. The further treatment is the same as in Example 1.

3. To hair or wool on the skin is applied, as in Example 1, an aqueous solution containing 5 to 10% of nitric acid acting as an acidulating agent, 3 to 5% of peroxide of hydrogen, acting as an oxygen carrier or oxidizing agent and 1 to 2% of tungsten onmol bdenum in the form of a tungstate or moly date soluble in water and acting as an oxygen conveyor the tungsten or molybdenic acid being oxidized by the peroxide of hydrogen to pertungstic or permolybdenic acid respec tively which gives 011 oxygen to the hair or WOOl being reduced to tungstic or molybdenic acid respectively and this is oxidized in turn by the peroxide of hydrogen and so on. The further treatment is the same as in Example 1.

4:. To as in Example 1, an a ueous solution con 'taining 2% by weight 0 potassium chlorate,

1% sulphuric acid and O.1% of chromium in the fiirm of chromic acid or of a bichromate solub e in water; the further treatment is the same as in Example 1.

5. To hair or Wool on the skin is applied, as in Example 1, an aqueous solution containing 4% by weight of ammonium persulphate, 2% sulphuric acid and 1% of chromium hair or vwool on the skin is applied,

alum. The further treatment is the same as in Example 1.

6. To hair or wool on the skin is applied of chromium in the form of chromic acid or of a bichromate. The further treatment is the same as in Example 1.

8. To hair or wool on the skin is applied, as in Example 1, an aqueous solution contain ing 3% by weight of ammonium persulphate 2% of sulphuric acid and 0.4% of chromium in the form of chromic acid or a bichromate.

In Examples 4 to 8 the potassium chlorate and ammonium persulphate act as oxygen carriers, the chromic acid bichromate and the chromium alum act as oxy enconveyors and the sulphuric and nitric acid act as acidulating agents.

The above described process is also applicable to hair or wool cut from the skin but in this case the concentrations above indicated will have to be notably reduced, say to one quarter or one tenth of those above given, according to the degree of concentration 'of the liquid remaining on the hair or wool after removal of the excess of liquid and according to the nature of the hair and wool treated.

I wish it to be understood that I do not claim the use of nitric acid and a metal or metai salt without the use of an oxidizing a en V What I claim is:

1. In cari-oting animal hair and wool the step comprlslng the application to the hair and wool of an aqueous solution of an oxygen carrier and of an oxygen conveyor and of nitric acid.

2. In carroting animal hair and wool the step comprising the a plication to the hair and wool a mixture 0 aqueous solutions of an oxygen carrier and of an oxygen conveyor and nitric acid.

. 3. In carroting animal hair and wool the step comprlsing the application to the hair and wool of an aqueous solution of an oxygen carrier and of an oxygen conveyor, such oxygen conveyor consisting of an oxygen compound of a metal having a plurality of degrees of oxygenation, those poorerin oxygen being readil' converted into those richer in oxygen b t e oxygen carrier and the compounds 0 such metals. richer in oxygen being ,capable of readily giving off oxygen to the hair and wool. V 4. In carroting animal heair and wool the step comprislng the application" to the hair and wool of an aqueous solution of an oxygen carrier and of an oxygen conveyor, such oxygen conveyor consisting of an oxygen compound of a metal of the chromic group.

5. In carroting animal hair or Wool the step comprising the application to the hair and Wool of an aqueous solution of an oxygen -arrier and of an oxygen conveyor, such oxygen conveyor consisting of a tungstate soluble in Water.

6. In carroting animal hair and Wool the step comprising the application to the hair and wool of an aqueous solution of an oxygen tl-lllCl and of an oxygen" conveyor, such oxy en conveyor consisting of a tungstate solu le' in water, the oxygen carrier consisting of peroxide of hydrogen.

In carroting animal hair and wool the:

ste comprising the application to the hair an' wool of an aqueous solution of an oxygen carrier and of, an oxygen conveyor, such oxygen conveyor consisting of a tungstate soluble in water, the oxygen carrier consisting of peroxide of hydrogen and an acidu latmg agent. r

8. In carroting animal hair and wool the step comprising the application to the hair and Wool of an aqueous solution of an oxygen carrier and of an oxygen conveyor, such oxygen conveyor consisting of a tungstate soluble in Water,- the oxygen carrier consisting of peroxide of hydrogen and nitric acid actin as an acid-ulating agent.

In testimony whereof I have aifixed', my

signature.

ERICH BOHM. 

